1. Field of the Invention
The present invention pertains to a portable louver forming tool for fabricating louvers or vents in sheet metal or other shape-holding material such as plastic.
2. Background of the Invention
Typically, vents or louvers are employed for ventilation purposes in such articles as automobile hoods, ventilation ducts, or housings around furnaces, air conditioners or other equipment. The louvers permit air to circulate, for example, from inside a particular enclosure to the outside of the enclosure as exemplified by louvers in housings around air conditioners, or permit air to circulate from outside to the inside of an enclosure as exemplified by louvers formed in hoods of automobiles such that when the automobile is moving, air is forced through the louvers into the engine compartment to help prevent overheating of the engine.
Generally, louvers and vents are formed by first cutting the sheet metal with a cutting or shearing blade and pressing the sheet metal into a die mold which shapes and forms the louvers. Such a typical procedure necessitates transporting the sheet metal to the louver fabricating device because all prior art louver forming tools required access to both sides of the sheet metal in order to cut and form the louvers or vents. If louvers are desired in a sheet metal enclosure after original assembly, it becomes difficult to dismantle the enclosure and transport the sheet metal enclosure to a louver fabricating tool.
U.S. Pat. No. 1,353,524 issued to Fleming, et al shows a typical machine for cutting vents in automobile hoods. This machine is designed to be mounted upon a stationary horizontal surface and is not meant to be portable. The device comprises a swing arm 4 and a cutting and shaping element 5. Both the swing arm and the cutting and shaping element mechanically relate to the die opening 19 which molds the sheet metal into the form of a louver. The sheet metal is placed between the cutting and shaping element 5 and the die opening 19. By pulling downwardly on handle 13 the cutting element 5 slits the sheet metal and presses the edges of the slit into the die opening 19, thus fabricating a louver. Different size louvers can be fabricated depending upon the selected size of the cutting and shaping element 5 and the corresponding die opening 19.
U.S. Pat. No. 2,728,316 to Oberg et al is directed to a combination shearing and pressing tool to produce ventilation openings. The tool comprises a punch 4 with a circular cutting edge 12 and a corresponding die element 5 which shapes the louver. The sheet metal is placed between the punch 4 and the die element 5. Handle 18 is pulled downwardly by an operator forcing the punch to slit the sheet metal and force an edge of the sheet metal into the corresponding die element 5 which forms and shapes the louver. This device is not portable.
U.S. Pat. No. 3,943,744 issued to Marsh et al shows a louver cutter with a cutting blade 40 and a die pad 14. Once the sheet metal is positioned between the cutting blade 40 and the die pad 14, handle 30 can be pulled in a clock-wise fashion causing blade 40 to slits the sheet metal and deform the metal into the shape of a louver opening. This tool is not portable.
As is noted by the prior art references, none of the prior art tools are capable of forming louvers in sheet metal or the like with a portable tool such that the louvers can be formed in situ. Also, none of the prior art tools teach the capability of forming a louver in sheet metal by merely having access to one side of the sheet metal, that is, all prior art tools of necessity require access to both sides of the sheet metal in order to fabricate a louver.